primidone

Question 1

what is it partially converted to

Answer 1

Primidone is partially converted to phenobarbital, but is also considered to have some antiepileptic action in its own right.

Question 2

cross sensitivity reported with this other AED

Answer 2

carb

Question 3

therapeutic drug monitoring

Answer 3

Monitor plasma concentrations of derived phenobarbital; plasma concentration for optimum response is 15–40 mg/litre (60–180 micromol/litre).

Question 4

which types of seizures is it used for

Answer 4

All forms of epilepsy except typical absence seizures

Question 5

important info re vitamin D

Answer 5

reduces the absorption of it
MHRA advises consider vitamin D supplementation in patients who are immobilised for long periods or who have inadequate sun exposure or dietary intake of calcium.

Question 6

does it affect EHC, COC

Answer 6

yes
Primidone is predicted to decrease the efficacy of Levonorgestrel. Double dose (unlicensed)

Primidone decreases the efficacy of Ulipristal. Manufacturer advises avoid and for 4 weeks after stopping the enzyme inducing drug.

Primidone is predicted to decrease the efficacy of Combined hormonal contraceptives.